~-RF power is usually transmitted into ,an accelerator section from a rectangular waveguide through a single coupling iris. This arrangement introduces phase and amplitude asymmetries into the coupler fields with which the beam interacts. Field distortion can be reduced by machining an offset into the cavity wall opposite the iris. However, the compensation is imperfect. In this paper we descri...

Patch hybrid couplers are used to provide arbitrary power division ratio over two frequency bands. The coupler is designed using three main topologies. They are Branch-line, Coupled-line and Patch. Branch-line and Coupled-line provides equal power division ratio over two frequency bands. Patch structure provides arbitrary power division ratios. The patch hybrid coupler is the rapid development ...

We propose and demonstrate an efficient coupler for compact mode conversion between a fiber and a submicrometer waveguide. The coupler is composed of high-index-contrast materials and is based on a short taper with a nanometer-sized tip. We show that the micrometer-long silicon-on-insulator-based nanotaper coupler is able to efficiently convert both the mode field profile and the effective inde...

We present a high power RF coupler design for an interleaved 2 805 MHz standing wave accelerating structure proposed for an muon cooling experiment at FNAL. The coupler, in its simplest form, is a rectangular waveguide directly connected to an accelerating cell through an open slot on the cavity side-wall or end-plates. Two of such couplers are needed to feed the interleaved cavities. Current h...

OBJECTIVE We present a case of exposure of a microvascular anastomotic coupler. METHODS We performed venous anastomoses using microvascular anastomotic couplers in head and neck reconstruction. RESULTS A microvascular anastomotic coupler was exposed in the seventh month postoperation, and an anastomosed vein was disrupted. CONCLUSIONS Although the usefulness of the microvascular anastomot...

A highly efficient, diode-pumped, Nd:YAG laser is described. The oscillator utilizes an unstable resonator design with a Gaussian reflectivity output coupler and a side-pumped zigzag slab gain medium. The laser produces 18-mJ, 10-ns pulses at a repetition rate of 242 Hz in a near-TEM00 mode with an optical efficiency of up to 14%. An extended performance test was recently concluded in which the...

Optical couplers are very important devices in optical communication systems and optical sensor systems. Several types of optical couplers with different materials or different transmission characteristics have been reported. Here we propose a semi-reciprocal polarization maintaining fibre coupler with unique transmission characteristics, which is distinct from conventional polarization maintai...

We present a C-band 6-mode 7-core fiber amplifier in an all-fiberized cladding-pumped configuration for space division multiplexed transmission supporting record 42 spatial channels. With optimized components (e.g. passively cooled pump laser diode, coupler, stripper), high power multimode light is coupled to the active without any noticeable thermal degradation and average gain of 18 dB noise ...

More than 60% overall coupling efficiency is achieved in the demonstrator of an optical interconnect comprising an input grating coupler, a multimode slab waveguide section and an output grating coupler. The grating coupling strength is enhanced by means of a leaky mode resonance. The efficiency of the resonant grating coupler compares favourably with the performancs reported on mirror inserts.

A method to improve the isolation of the microstrip coupler is presented. The pattern of the coupler is modified for phase velocity compensation which results in high isolation. Using this procedure, a 15 dB coupler is designed and fabricated at 0.9 GHz. A high isolation of 63.3 dB is measured. The validity of the design concept is verified by simulations and measurements.